Synthesis of Grafted Hydrogels as Mono-Divalent Cation Exchange for Drug Delivery

Abstract

pH-sensitive acrylic acid grafted polyvinylalcohol (AAc-g-PVA) hydrogels has been prepared by gamma irradiation. The maximum grafting yield was at monomer concentration 50% and dose 50 kGy. The swelling, network parameters, thermogravimetric analysis, activation energy and scanning electron microscope of the grafted hydrogels were evaluated. Hydrogel demonstrate high swelling at pH 6.8. The deswelling of the swollen gel in Ni²⁺ and Cu²⁺ cations solution was explained on the basis of mono-divalent cation exchange. The release of antihistaminic chlorphenamine maleate hydrochloride (CPM) was faster in gastric fluid (SGF) of pH 1.1 than in intestinal fluid (SIF) of pH 6.8.

Keywords:

• Chlorphenamine maleate
• Grafted hydrogels
• Swelling
• Thermal stability